Technical Ducato 2.8JTD power loss

[Anthony489]

Hi

The rattle (oscillaton) will occur when you have a resonant mechanical system (i.e. a spring and a mass) and it is excited in some way, in this case by the gas pressure under certain conditions. If there is a bit of friction in the system it will tend to dampen the oscillation, which is good. Not too much friction though, or the actuator will not be able to move it properly. Any free play (maybe a little bit of wear in the spindle bush) will tend to increase oscillation. Light lubricant like WD40 may reduce the friction, which is maybe not what you want. On the other hand, if there is drag from heavy grease this will dampen the oscillation, which is useful. I am not sure if there is a type of grease which can withstand the high temperatures and still be heavy (viscous) enough to give damping in the long term.

Some people have cured the noise by fitting a small coil spring to pull the actuating lever sideways. Maybe this compensates for the play in the spindle bush, by keeping the spindle biased to one side of the bush where it will have metal-on-metal friction ?

I cannot see how the oscillation/rattle can affect the average boost by very much, unless the movement is quite large. Only a small video camera and monitor would let you see it while driving.

Thinking about other causes, your symptoms suggest something that comes and goes. This is typical of poor electrical contacts, which are sensitive to heat and vibration. Without seeing your van, I cannot suggest where to look but I agree the injectors would be a good start as they draw high peak currents so are sensitive to poor connections. This is a bit surprising, as the pictures and videos of your van show it to be very clean underneath and suggest it has been kept indoors most of its life !

The throttle pedal normally has two potentiometers with separate wires back to the ECU. The ECU compares the signals from the potentiometers, to make sure they are the same (or almost the same). If they are too different, it will store an error code but may still allow driving.

 

[corsedanny]

Hi

The rattle (oscillaton) will occur when you have a resonant mechanical system (i.e. a spring and a mass) and it is excited in some way, in this case by the gas pressure under certain conditions. If there is a bit of friction in the system it will tend to dampen the oscillation, which is good. Not too much friction though, or the actuator will not be able to move it properly. Any free play (maybe a little bit of wear in the spindle bush) will tend to increase oscillation. Light lubricant like WD40 may reduce the friction, which is maybe not what you want. On the other hand, if there is drag from heavy grease this will dampen the oscillation, which is useful. I am not sure if there is a type of grease which can withstand the high temperatures and still be heavy (viscous) enough to give damping in the long term.

Some people have cured the noise by fitting a small coil spring to pull the actuating lever sideways. Maybe this compensates for the play in the spindle bush, by keeping the spindle biased to one side of the bush where it will have metal-on-metal friction ?

I cannot see how the oscillation/rattle can affect the average boost by very much, unless the movement is quite large. Only a small video camera and monitor would let you see it while driving.

Thinking about other causes, your symptoms suggest something that comes and goes. This is typical of poor electrical contacts, which are sensitive to heat and vibration. Without seeing your van, I cannot suggest where to look but I agree the injectors would be a good start as they draw high peak currents so are sensitive to poor connections. This is a bit surprising, as the pictures and videos of your van show it to be very clean underneath and suggest it has been kept indoors most of its life !

The throttle pedal normally has two potentiometers with separate wires back to the ECU. The ECU compares the signals from the potentiometers, to make sure they are the same (or almost the same). If they are too different, it will store an error code but may still allow driving.

Thanks for your welcome feedback Anthony!

Yesterday i found information regarding, indeed, an electronical issue between injection control unit and throttle pedal.. today i removed a certain connector and put all wires together.. its good and tight, but not on the nicest way as i cant solder here. Started the car and worked, but cant drive atm so couldnt really test this yet. It comes from the Netherlands this information, specifically the id number of the vehicle starting with a certain number has this issue (which includes mine), on that forum literally everyone got their problem solved. The only thing is that i havent seen my injection warning light going on at the dash. Which most others did have.

The forum is in Dutch, but i am willing to share the link if you want. If this turns out to be helpfull, i will post a guide of how to do this here, for future cases so people know what to try .

 

[corsedanny]

Small update from my side.

I have deinstalled a certain connector between the throttle pedal potentiometer going to the injection control unit.. yesterday evening (colder air temps) i did a testdrive and yes i did have turbo power back!

I will, for those with x230 Ducatos, make a short manual of what to do when you experience these problems and for sure when you have your injector wqrning light coming on.

So a big step forward seems to be made. With cold engine though, i have quite a bit of Turbo whine going on and i am also not yet satisfied with how smoothly the engine is operating. This can still be improved.

I wonder if anybody knows whether i have the old injector connectors or the ones that were built in as a replacement. Hope anybody knows this..

 

[Exit04]

Thanks for your welcome feedback Anthony!

Yesterday i found information regarding, indeed, an electronical issue between injection control unit and throttle pedal.. today i removed a certain connector and put all wires together.. its good and tight, but not on the nicest way as i cant solder here. Started the car and worked, but cant drive atm so couldnt really test this yet. It comes from the Netherlands this information, specifically the id number of the vehicle starting with a certain number has this issue (which includes mine), on that forum literally everyone got their problem solved. The only thing is that i havent seen my injection warning light going on at the dash. Which most others did have.

The forum is in Dutch, but i am willing to share the link if you want. If this turns out to be helpfull, i will post a guide of how to do this here, for future cases so people know what to try .

@corsedanny..

Hi..
Did you ever make a guide for the faulty TPS connector fault..?
I have a 2002 2.8 JTD Rollerteam Motorhome with the 8140.43S diesel engine and have been having the injector warning light coming on intermittently when accelerating during overtaking and also on steep hill climbs. It is accompanied by power-loss which varies in length of time.. but IS worrying especially during overtakes !
Buying at the end of 2019 just before the Pandemic meant I didn't drive it much until lockdown's stopped so to be honest I thought it was just an 'over-revving' indicaton I was seeing. However since following your posting about power-loss I am now thinking to find that TPS connector and fix what now appears to be a problem. I have removed the lower dash on both driver and passenger sides to try to find said connector but someone has already been in there modifying wiring and it's a complete mess(!).. and hard to follow.

The information.. photos and videos in your posts were very helpful and I've added them to my computer for future reference.. so thanks for those.

My Ducato is of course right-hand-drive for UK so the wiring might take a slightly different path.. but any information you have on identifying the problem connector would be helpful.
regards
Tony

 

[corsedanny]

@corsedanny..

Hi..
Did you ever make a guide for the faulty TPS connector fault..?
I have a 2002 2.8 JTD Rollerteam Motorhome with the 8140.43S diesel engine and have been having the injector warning light coming on intermittently when accelerating during overtaking and also on steep hill climbs. It is accompanied by power-loss which varies in length of time.. but IS worrying especially during overtakes !
Buying at the end of 2019 just before the Pandemic meant I didn't drive it much until lockdown's stopped so to be honest I thought it was just an 'over-revving' indicaton I was seeing. However since following your posting about power-loss I am now thinking to find that TPS connector and fix what now appears to be a problem. I have removed the lower dash on both driver and passenger sides to try to find said connector but someone has already been in there modifying wiring and it's a complete mess(!).. and hard to follow.

The information.. photos and videos in your posts were very helpful and I've added them to my computer for future reference.. so thanks for those.

My Ducato is of course right-hand-drive for UK so the wiring might take a slightly different path.. but any information you have on identifying the problem connector would be helpful.
regards
Tony

Hello Tony,

In what you desribe above, I would not search any further than the connectors on the injectors. Order and replace those and I am 99,9% sure that your problem is solved again for the upcoming 100.000km or 60.000miles.

 

[Exit04]

Hello Tony,

In what you desribe above, I would not search any further than the connectors on the injectors. Order and replace those and I am 99,9% sure that your problem is solved again for the upcoming 100.000km or 60.000miles.

Hello Danny and thanks for your reply..

I have already checked the injector connectors. None were overstretched by any means. They seem fine and contacts were very clean. I applied contact cleaner to them anyway.
However.. I would still like to locate the under-dash 6 wire TPS connector you mention in some of your posts as you said those on the (netherlands) forum who deleted this connector and soldered the wires solved their similar problem.
Any help in that direction would be welcome but if not then I guess I will just have to try to sort through the 'rats-nest' of wiring that is under my dash ubtil I locate it (!) It's just not easy for me physically..
regards
Tony

 

[corsedanny]

Hello Danny and thanks for your reply..

I have already checked the injector connectors. None were overstretched by any means. They seem fine and contacts were very clean. I applied contact cleaner to them anyway.
However.. I would still like to locate the under-dash 6 wire TPS connector you mention in some of your posts as you said those on the (netherlands) forum who deleted this connector and soldered the wires solved their similar problem.
Any help in that direction would be welcome but if not then I guess I will just have to try to sort through the 'rats-nest' of wiring that is under my dash ubtil I locate it (!) It's just not easy for me physically..
regards
Tony

Hello Exit04,

Your symptoms as you are describing are (in my best knowledge) for sure not coming from a faulty connector from your TPS towards your ECU. And even though the connectors look fine, I am pretty sure you will find that issue in those as what you describe is basically matching for 100% with all other cases I know with these connector failures.

But ofcourse I can try to help you with finding that connector, the only difference is you having an English car which is right hand drive. I don't dare to say what has all changed sides. But the wires go basically from your throttle pedal potentiometer to your ECU and in the middle somewhere is a white plastic connector which could be a faulty one. Remind you, this happened basically only on Ducato 230 models. Is yours a 230 or already a 244 model?

I would remove (in your case) both lower parts of the dashboard. Then go to your throttle pedal where you will find a connector inside your throttle pedal. That's your throttle pedal potentiometer. From there you can see the colours of the wires and maybe note them down and try to follow those cables as well as you can untill the moment you see them coming together in a white connector that lays on top of the left or right shockabsorber with a bunch of other connectors.

Please let us know the result!

GReetings
Danny